The Microarray Shared Resource was created in 1999 to support Mayo Cancer Center Investigators needs for global transcriptional profiling. The major services provided include gene-expression profiling using Affymetrix GeneChips, and verification of expression levels by real-time PCR methods, and quality assessment procedures for RNA. Data analysis has been added as a service in 2003. Services available on a custom basis include custom spotting of oligonucleotide and cDNA microarrays, and hybridization and analysis of BAC assays. Since 2000, the Microarray Shared Resource has supported experiments from over 50 MCCC Investigators. In 2002, investigators from 6 Cancer Center Programs utilized this Shared Resource. Greatest usage in 2002 and 2003 has been from members of the Prostate Cancer and Hematologic Malignancies Programs. The goals for the Microarray Shared Resource are to bring state-of the art improvements in genomics approaches to research in oncology. This includes: i. increasing the sensitivity and specificity of gene-expression profiling experiments by routinely using laser-captured micro-dissected tissues; ii. assessing feasibility of utilizing paraffin-embedded materials; iii. improving the sensitivity of transcriptional profiling for low copy-number transcripts using oligonucleotide microarrays; iv. analysis of small chromosome regions with custom-fabricated BAC microarrays; v. expanding data analysis capacity and sophistication.